BACKGROUND: Lichen sclerosus is characterized by a collagenous hyaline/homogeneous zone at upper dermis, which remains undefined morphologically and biologically. Our previous investigation showed that there are several changes at the extracellular matrix hyaline zone, such as accumulation of collagenic proteins (types I and III) and sulfated proteoglycans/glycosaminoglycans. OBJECTIVES: Decorin and chondroitim sulfate (sulfated proteoglycans/glycosaminoglycans) immunoexpressions were the present investigation´s aim, emphasizing the hyaline zone related changes. METHODS: Thirty one vulvar LS untreated clinical lesions were biopsed and evaluated histologically according to Hewitt’s gradation and by immunohistochemical methods. Results were compared with ones of the control group, which was formed by cutaneous fragments from vulvoperineal corrective surgeries. RESULTS: We could demonstrate that decorin and chondroitin sulfate were present at the hyaline zone in different moments of matrix modulation. In all Hewitt stages chondroitin sulfate prevailed at the extracellular matrix in cases with a compact aspect of the hyaline zone while decorin was only seen in areas of less compactness. CONCLUSION: This proteoglycans/glycosaminoglycans synthesis sequence suggests that decorin may be a possible initial marker/indicator for vulvar LS. We suppose either that chondroitin sulfate is possibly a factor that limit matricial changes extension till middle dermis level.
Glycosaminoglycans; Lichen sclerosus et atrophicus; Extracellular matrix; Proteoglycans; Vulva
